GEN 2TABLES AND CODES

GEN 2.1MEASURING SYSTEM, AIRCRAFT MARKINGS, HOLIDAYS

1Units of measurement

The table of units of measurement shown below is used within Tallinn FIR for air and ground operations.

For measurement of

Units used

Distance used in navigation, position reporting, etc - generally in excess of 2 NM

Nautical Miles (NM) and tenths

Relatively short distances such as those relating to aerodromes (e.g., runway lengths)

Metres (m)

Altitudes, elevations and heights

Feet (ft)

Horizontal speed including wind speed

Knots (kt)

Vertical speed

Feet per minute (ft/min)

Wind direction for landing and taking off

Degrees Magnetic (°)

Wind direction except for landing and taking off

Degrees True (°)

Visibility, incl. runway visual range

Kilometres or metres (km or m)

Altimeter setting

Hectopascal (hPa)

Temperature

Degrees Celsius (°)

Weight

Metric tonnes or Kilogrammes (t or kg)

Time

Hours (HR) and minutes (min); beginning at midnight UTC

Volume

Litre (L)

The dimensional units are in accordance with Annex 5.

2Temporal reference system

Co-ordinated Universal Time (UTC) and the Gregorian calendar are used by air navigation services and in publications issued by the Aeronautical Information Service. Reporting of time is expressed to the nearest minute, e.g., 12:40:35 is reported as 1241.

In the AIP and associated publications, the expression “summer period” will indicate that part of the year in which “daylight saving time” is in force. The other part of the year will be named the “winter period”.

Daylight saving time in Estonia is UTC + 3 hours.

The “summer period” will be introduced every year on the last Sunday in MAR at 0100 UTC and it will cease on the last Sunday in OCT at 0100 UTC. Times applicable during “summer period” are given in brackets.

Local time in Estonia is UTC + 2 hours.

3Horizontal reference system

3.1Name/designation of the reference system

All geographical coordinates indicating latitude and longitude published in AIP and aeronautical charts are expressed in terms of the World Geodetic System-1984 (WGS-84) geodetic reference datum.

3.2Identification of the projection

Projection is expressed in terms of Lambert conformal conic projection with two reference secant parallels LAMBERT-ESTONIA (LAMBERT-EST), calculations of which are made based on the ellipsoid GRS80 using following numerical data:

1.

central Meridian

LC=24°00’E

2.

first Standard Parallel

BS=58°00’N

3.

second Standard Parallel

BS=59°20’

4.

geodetic coordinates of the reference point

B0=57°31’03’’.19415N L0=24°00’E

3.3Identification of the ellipsoid used

Geodetic Reference System 1980 (GRS80) ellipsoid is used.

3.4Identification of the datum used

The World Geodetic System-1984 (WGS-84) is used.

3.5Area of application

The area of application for the published geographical coordinates coincides with the area of responsibility of the Aeronautical Information Service, i.e the entire territory of Estonia as well as the airspace over the high seas encompassed by the Tallinn FIR in accordance with the regional air navigation agreement.

3.6Use of an asterisk to identify published geographical coordinates

An asterisk (*) will be used to identify those published geographical coordinates which have been transformed into WGS-84 coordinates but whose accuracy of original field work does not meet the requirements in ICAO Annex 11, Chapter 2 and ICAO Annex 14, Volumes I and II, Chapter 2.

Specifications for determination and reporting of WGS-84 coordinates are given in ICAO Annex 11, Chapter 2 and in ICAO Annex 14, Volumes I and II, Chapter 2.

4Vertical Reference Datum

4.1Name/Designation of the Reference System

The vertical reference system used is EH2000, which corresponds to mean sea level (MSL).

4.2Description of the Geoid Model Used

The geoid model EST-GEOID2017 is used.

4.3Differences Between the Altitudes Referenced to EST-GEOID2017 and EGM96 in Estonia

The differences between the orthometric heights referenced to EST-GEOID2017 and the orthometric heights referenced to EGM96 (that is, the differences between the undulations of both geoids) depend on the geographic location of the point under consideration. The following map shows the undulation differences of these models in Estonia.

5Aircraft Nationality and Registration Marks

The nationality mark for aircraft registered in Estonia consists of the letters ES. The nationality mark is followed by a hyphen and a registration mark consisting of 3 letters, e.g., ES-ABC, or 4 numbers, e.g., ES-1234.